/Engine/Plugins/Runtime/RigVM/Source/RigVMDeveloper/Public/RigVMCompiler/RigVMAST.h
An abstract syntax tree no-op expression represents an expression which is relevant for the structure of the tree (for grouping for example) but which itself has no operation connected to it. For the RigVM AST we use the no-op expression for representing reroute nodes in the model as well as parameter and variable getter nodes.
class FRigVMNoOpExprAST : public [FRigVMNodeExprAST](API\Plugins\RigVMDeveloper\RigVMCompiler\FRigVMNodeExprAST)